Identification of bacteria in aquatic and environmental applications, for monitoring purposes and research, for health assessments and therapy considerations of farmed and free-living aquatic organisms, still relies on conventional phenotypic and biochemical protocols. Although molecular techniques based on DNA amplification and sequencing are finding ways into diagnostic laboratories, they are time-consuming, costly and difficult in the case of multiplex assays. Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) is a rapid and accurate proteomic method reliable for identification of unknown bacteria to the genus and species level. Upon extension of databases, it will certainly find its position in environmental sciences. The paper presents an overview of the principle of the method, its effectiveness in comparison with conventional and molecular identification procedures, and applicability on environmental and aquatic isolates, discussing its advantages and shortcomings, as well as possible future implementations.

S-layers represent the simplest biological membranes developed during the evolution and are one of the most abundant biopolymers on Earth. Current fundamental and applied research aim to reveal the chemical structure, morphogenesis and function of S-layer proteins (Slps). This is the first paper that describes the Slps of certain Lactobacillus brevis strain isolated from sauerkraut. The whole genome sequence (WGS) analysis of the L. brevis SF9B strain uncovered three genes encoding the putative Slps, but merely one, identified as similar to the SlpB of L. brevis ATCC 14869, was expressed. Slp-expressing SF9B cells exhibited increased survival in simulated gastrointestinal

Acinetobacter baumannii is an emerging hospital pathogen. Whereas A. baumannii isolated from patients or hospitals has been reported, there are few data regarding propagation of viable A. baumannii in the natural environment. This study investigates the occurrence and antimicrobial susceptibility of viable A. baumannii in municipal wastewater and its persistence through the wastewater treatment process. A total of 21 A. baumannii isolates were recovered at a secondary type of municipal wastewater treatment plant in Zagreb, Croatia: 15 from raw influent wastewater and six from final effluent. All isolates were carbapenem- and multidrug-resistant. Among 14 isolates tested for blaOXA genes, all harboured the constitutive blaOXA-51-like gene, while the acquired blaOXA-23-like and blaOXA-40-like genes were found in 10 and three isolates respectively. Six A. baumannii isolates recovered from effluent wastewater multiplied and survived in sterilised effluent wastewater up to 50 days. These findings support the idea that multidrug-resistant A. baumannii can occur and have the ability to survive in the environment.

The study focuses on developing novel cottage cheese containing spices with acceptable sensory properties, increased biological value and extended shelf life. Thirty types of cheese with added fresh or dried parsley, dill, pepper, garlic and rosemary were produced. Characterisation of phenolic compounds, antioxidant capacity and antibacterial activity of spices and cheese samples were evaluated. The cheese containing fresh pepper and fresh and dried herbs showed excellent sensory properties, with the best results obtained with fresh sweet red pepper. Dry rosemary had the highest antioxidant and antibacterial activity due to high mass fractions of caffeic and rosmarinic acids as well as high mass fractions of flavones and phenolic diterpenes. The plant extracts examined and effectively reduce numbers of foodborne pathogens like ,, , and therefore have potential as natural preservatives and antioxidants.

Two series of new dicyclopalladated complexes {(DMF)PdCl(μ-R(1)C6H3N═NC6H3R(2))PdCl(DMF)} of 4,4'-functionalized azobenzenes with substituents of varying electron-donating or electron-withdrawing strength (R(1) = H, NMe2; R(2) = H, Cl, Br, I, OMe, PhNH, CO2H, SO3Na, or NO2) have been synthesized and fully characterized. (1)H NMR spectroscopy along with the ESI mass spectrometry unambiguously identified the new complexes in the solution, and their solid-state structures were determined by X-ray crystallography. The presence of easily exchangeable solvent ligands was confirmed by (1)H NMR spectroscopy, X-ray experiments, and ESI mass spectrometry. The complexes were additionally characterized by UV-vis and fluorescence spectroscopies. The effect of different 4,4'-substituents on the formation rate of mono- and dicyclopalladated azobenzenes was studied by UV-vis spectroscopy. The experimental results are complemented by the quantum-chemical (DFT) calculations in order to rationalize the kinetic results as well as substituent effects on the reaction rates. It was found that the mono- and dicyclopalladation reactions of azobenzenes proceed in two consecutive processes, adduct formation and palladation steps. The rate-determining step in both palladations is the breaking of the ortho C-H bond, which has been confirmed as an electrophilic substitution process by Hammett correlations and DFT calculations.